METHOD OF SANDWICHED COATING OBTAINMENT FOR CUTTING TOOL Russian patent published in 2015 - IPC C23C14/06 C23C14/24 B23B27/14 

FIELD: metallurgy.

SUBSTANCE: sandwiched coating is applied by vacuum plasma method. Lower layer of niobium carbide is applied first. Further, top layer of titanium, silicon and chrome composition nitride is applied at the following component ratio, wt %: titanium 87.1-90.5, silicon 1.0-1.4, niobium 8.5-11.5. Coating layers are applied by three cathodes arranged horizontally in the same plane. First cathode is made of titanium and silicon alloy, second cathode is made of niobium and opposed to the first cathode, while third cathode is made of titanium and chrome and positioned between the first and second cathodes. Bottom layer is applied by the second cathode, while top layer is applied by the first and the third cathodes.

EFFECT: higher cutting tool efficiency.

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